South Sudan has missed a key deadline to create a transitional government, after the president increased the number of provinces from 10 to 28.
The plan for a unity government was part of a peace deal in August to end the civil war which began in 2013 when President Salva Kiir accused his then-deputy Riek Machar of plotting a coup.
The two sides blame each other for violating the terms of the agreement.
Thousands of people have been killed and millions displaced since 2013.
President Kiir, who said he had "reservations" about the August peace deal, appointed 28 new governors for the new provinces, just as rebel delegates arrived in the capital Juba, to begin work on the new government.
The former president of Botswana and head of the Joint Monitoring and Evaluation Commission, Festus Mogae, told Al Jazeera the move was one of the many barriers to peace.
"One important one that has occurred, unfortunate in its timing, is the creation of 28 states because it's inconsistent with what is envisaged in the [peace] agreement and, therefore, it is not acceptable," Mr Mogae said.
The United Nations released a report this week, accusing both President Kiir's forces and Mr Machar's rebels of mutual killings, including "hundreds of extra-judicial killings, enforced disappearances, gang-rapes, sexual slavery, forced abortion, [and] massive child soldier recruitment".
Peter Schumann, former director of the UN Mission in Southern Sudan told All Africa he would have been surprised if the transitional government had been established.
"Both parties have different agendas and do not follow their agreements," Mr Schumann said. "There is no peaceful solution, because both parties are trying to control territory and oil resources."